<!DOCTYPE html>
<html>
<head>
  <meta charset="UTF-8">
  <title>Document</title>
  <style>
    
  </style>
</head>
<body>
  
</body>
<script>
  
  var obj = {};
  console.log( {} );
  console.log( obj + "world" );

  console.log("=====");
  
  // var str = new String("hello");
  var str = "hello";
  console.log( typeof str );
  console.log( str );
  console.log( str + " world" );

  console.log(str.length)
  for(var i=0;i<str.length;i++){
    console.log(str[i])
  }
  
  console.log("=====");
  
  var num = new Number(365);
  console.log( typeof num );
  console.log( num );
  console.log( num + 1 );
  
  console.log("=====");

  var bool = new Boolean(false);
  console.log( typeof bool );
  console.log( bool );
  if(bool){
    console.log(1);
  }else{
    console.log(2);
  }


  
</script>
</html>